One form of needle selector apparatus for a Jacquard machine comprises a plurality of vertically movable drop needles, and thrust needles which are mounted therein and which are thus movable vertically and also horizontally by way of control devices. A respective blocking element is associated with an end of each drop needle in such a way as selectively to provide support for the end of the drop needle in a first support position or permit the drop needle to drop down in a second release or drop-down position The adjusting element of each blocking element which provides for displacement thereof between the first and second positions is a respective piezoelectric flexural transducer which is stationarily clamped at one end. A needle selector apparatus for Jacquard machines of that kind is to be found in DE 37 05 738 Al wherein the piezoelectric flexural transducers are disposed extending in the longitudinal direction of the drop needles, that is to say vertically, and are each stationarily clamped by means of their lower end. The upper free end of each of the piezoelectric flexural transducers can be pivoted by way of an electrical control device between the support or blocking position in which the ends of the drop needles come to bear against the respective flexural transducer and the release or drop-down position in which the respective piezoelectric flexural transducer is outside the path of movement of the respective drop needle.
That arrangement involves a structural configuration which takes up a great deal of space, more particularly especially in the longitudinal direction of the drop needles.